Asda`s three week £2 promotion on whole chickens prompted its sales to double, the chain said.

But a British Poultry Council spokesman warned that an ongoing supermarket poultry price war would be bad news for farmers. "It is not sustainable. We are not in such a bad situation as the dairy sector but agriculture is not in general in a good place following bird flu, flooding, high temperatures and the foot and mouth disease outbreak," British Poultry Council executive officer Jeremy Blackburn said.

Asda`s price deal, which ended yesterday, offered 1.55kg whole chickens for £2.

Tesco recently cut the price of its whole medium frozen chicken to £1.92 - around £1.28 per kg, according to trade magazine The Grocer.

But Mr Blackburn said the cheaper prices didn`t mean the poultry meat was poor quality.